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Unop

Unopp

Recognizer for unop structures.

Signature
(unopp x) → *

Definitions and Theorems

Function: unopp

(defun unopp (x)
  (declare (xargs :guard t))
  (and (consp x)
       (cond ((or (atom x) (eq (car x) :address))
              (and (eq (cdr x) nil) (b* nil t)))
             ((eq (car x) :indir)
              (and (eq (cdr x) nil) (b* nil t)))
             ((eq (car x) :plus)
              (and (eq (cdr x) nil) (b* nil t)))
             ((eq (car x) :minus)
              (and (eq (cdr x) nil) (b* nil t)))
             ((eq (car x) :bitnot)
              (and (eq (cdr x) nil) (b* nil t)))
             ((eq (car x) :lognot)
              (and (eq (cdr x) nil) (b* nil t)))
             ((eq (car x) :preinc)
              (and (eq (cdr x) nil) (b* nil t)))
             ((eq (car x) :predec)
              (and (eq (cdr x) nil) (b* nil t)))
             ((eq (car x) :postinc)
              (and (eq (cdr x) nil) (b* nil t)))
             ((eq (car x) :postdec)
              (and (eq (cdr x) nil) (b* nil t)))
             ((eq (car x) :sizeof)
              (and (eq (cdr x) nil) (b* nil t)))
             ((eq (car x) :alignof)
              (and (b* ((uscores (cdr x)))
                     (keyword-uscores-p uscores))))
             ((eq (car x) :real)
              (and (eq (cdr x) nil) (b* nil t)))
             (t (and (eq (car x) :imag)
                     (and (eq (cdr x) nil))
                     (b* nil t))))))

Theorem: consp-when-unopp

(defthm consp-when-unopp
  (implies (unopp x) (consp x))
  :rule-classes :compound-recognizer)